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                                                                   EXHIBIT 4.2.4

                          FOURTH SUPPLEMENTAL INDENTURE

         FOURTH SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"), dated as
of September 30, 2003 among Southern Construction Products, Inc., an Alabama
corporation ("Southern"), a subsidiary of Dayton Superior Corporation (or its
permitted successor), an Ohio corporation (the "Company"), the Company, the
other Guarantors (as defined in the Indenture, the First Supplemental Indenture,
the Second Supplemental Indenture and the Third Supplemental Indenture referred
to herein, each a "Guaranteeing Subsidiary," and collectively, the "Guaranteeing
Subsidiaries") and The Bank of New York as successor in interest to United
States Trust Company of New York, as trustee under the Indenture referred to
herein (the "Trustee").

                                   WITNESSETH:

         WHEREAS, the Company, Symons Corporation, a Delaware corporation
("Symons"), as a Guarantor, and Dur-O-Wal, Inc., a Delaware corporation
("Dur-O-Wal"), as a Guarantor, have heretofore executed and delivered to the
Trustee an indenture (the "Indenture"), dated as of June 16, 2000 providing for
the issuance of an aggregate principal amount of up to $270.0 million of 13%
Senior Subordinated Notes due 2009 (the "Notes");

         WHEREAS, the Company and Dayton Superior Specialty Chemical
Corporation, a Kansas corporation ("DSSCC"), as a Guarantor, have heretofore
executed and delivered to the Trustee a supplemental indenture (the "First
Supplemental Indenture"), dated as of August 3, 2000, which supplemented the
Indenture and added DSSCC as guarantor under the Indenture;

         WHEREAS, the Company, Trevecca Holdings, Inc., a Delaware corporation
("Trevecca"), as a Guarantor, and Aztec Concrete Accessories, a California
corporation ("Aztec"), as a Guarantor have heretofore executed and delivered to
the Trustee a supplemental indenture (the "Second Supplemental Indenture"),
dated as of January 4, 2001, which supplemented the Indenture and added Trevecca
and Aztec as guarantors under the Indenture;

         WHEREAS, the Company, Symons, as a Guarantor, Dur-O-Wal, as a
Guarantor, Trevecca, as a Guarantor, Aztec, as a Guarantor and DSSCC, as a
Guarantor have heretofore executed and delivered to the Trustee a supplemental
indenture (the "Third Supplemental Indenture"), dated as of June 19, 2001, which
supplemented the Indenture and added certain additional subsidiaries of the
Company as guarantors under the Indenture.

         WHEREAS, the Indenture provides that under certain circumstances each
Guaranteeing Subsidiary shall execute and deliver to the Trustee a supplemental
indenture pursuant to which each Guaranteeing Subsidiary shall unconditionally
guarantee all of the Company's Obligations under the Notes and the Indenture on
the terms and conditions set forth herein (the "Guarantee"); and

         WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

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         NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, each
Guaranteeing Subsidiary and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

         1. CAPITALIZED TERMS. Capitalized terms used herein without definition
shall have the meanings assigned to them in the Indenture.

         2. AGREEMENT TO GUARANTEE. Each Guaranteeing Subsidiary hereby agrees
as follows:

                  (a) Along with all Guarantors named in the Indenture, to
         jointly and severally Guarantee to each Holder of a Note authenticated
         and delivered by the Trustee and to the Trustee and its successors and
         assigns, irrespective of the validity and enforceability of the
         Indenture, the Notes or the Obligations of the Company hereunder or
         thereunder, that:

                           (i) the principal of, premium, if any, and interest
         on the Notes will be promptly paid in full when due, whether at
         maturity, by acceleration, redemption or otherwise, and interest on the
         overdue principal of and interest on the Notes, if any, if lawful, and
         all other Obligations of the Company to the Holders or the Trustee
         hereunder or thereunder will be promptly paid in full or performed, all
         in accordance with the terms hereof and thereof; and

                           (ii) in case of any extension of time of payment or
         renewal of any Notes or any of such other Obligations, that same will
         be promptly paid in full when due or performed in accordance with the
         terms of the extension or renewal, whether at stated maturity, by
         acceleration or otherwise. Failing payment when due of any amount so
         guaranteed or any performance so guaranteed for whatever reason, the
         Guarantors shall be jointly and severally obligated to pay the same
         immediately.

                  (b) The Obligations hereunder shall be unconditional,
         irrespective of the validity, regularity or enforceability of the Notes
         or the Indenture, the absence of any action to enforce the same, any
         waiver or consent by any Holder of the Notes with respect to any
         provisions hereof or thereof, the recovery of any judgment against the
         Company, any action to enforce the same or any other circumstance which
         might otherwise constitute a legal or equitable discharge or defense of
         a guarantor.

                  (c) The following is hereby waived: diligence, presentment,
         demand of payment, filing of claims with a court in the event of
         insolvency or bankruptcy of the Company, any right to require a
         proceeding first against the Company, protest, notice and all demands
         whatsoever.

                  (d) This Guarantee shall not be discharged except by complete
         performance of the Obligations contained in the Notes and the Indenture
         or pursuant to Section 6 hereof.

                  (e) If any Holder or the Trustee is required by any court or
         otherwise to return to the Company, the Guarantors, or any custodian,
         Trustee, liquidator or other similar official acting in relation to
         either the Company or the Guarantors, any amount paid by

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         either to the Trustee or such Holder, this Guarantee, to the extent
         theretofore discharged, shall be reinstated in full force and effect.

                  (f) Each Guaranteeing Subsidiary shall not be entitled to any
         right of subrogation in relation to the Holders in respect of any
         Obligations guaranteed hereby until payment in full of all Obligations
         guaranteed hereby.

                  (g) As between the Guarantors, on the one hand, and the
         Holders and the Trustee, on the other hand, (x) the maturity of the
         Obligations guaranteed hereby may be accelerated as provided in Article
         6 of the Indenture for the purposes of this Guarantee, notwithstanding
         any stay, injunction or other prohibition preventing such acceleration
         in respect of the Obligations guaranteed hereby, and (y) in the event
         of any declaration of acceleration of such Obligations as provided in
         Article 6 of the Indenture, such Obligations (whether or not due and
         payable) shall forthwith become due and payable by the Guarantors for
         the purpose of this Guarantee.

                  (h) The Guarantors shall have the right to seek contribution
         from any non-paying Guarantor so long as the exercise of such right
         does not impair the rights of the Holders under the Guarantee.

                  (i) Pursuant to Section 11.03 of the Indenture, the
         Obligations of a Guaranteeing Subsidiary shall be limited to such a
         maximum amount as after giving effect to any maximum amount and any
         other contingent and fixed liabilities that are relevant under any
         applicable Bankruptcy or fraudulent conveyance laws (including, without
         limitation, all Senior Debt of such Guarantor), and after giving effect
         to any collections from, rights to receive contribution from or
         payments made by or on behalf of any other Guarantor in respect of the
         Obligations of such other Guarantor under Article 11 of the Indenture,
         shall result in the Obligations of such Guarantor under its Guarantee
         not constituting a fraudulent transfer or conveyance.

         3. SUBORDINATION. The Obligations of each Guaranteeing Subsidiary under
its Guarantee pursuant to this Supplemental Indenture shall be junior and
subordinated to the Senior Debt of each Guaranteeing Subsidiary on the same
basis as the Notes are junior and subordinated to the Senior Debt of the
Company. For the purposes of the foregoing sentence, the Trustee and the Holders
shall have the right to receive and/or retain payments by each Guaranteeing
Subsidiary only at such time as they may receive and/or retain payments in
respect of the Notes pursuant to the Indenture, including Article 10 thereof.

         4. EXECUTION AND DELIVERY. Each Guaranteeing Subsidiary agrees that the
Guarantees shall remain in full force and effect notwithstanding any failure to
endorse on each Note a notation of such Guarantee.

         5. GUARANTEEING SUBSIDIARY MAY CONSOLIDATE, ETC. ON CERTAIN TERMS.

                  (a) Each Guaranteeing Subsidiary may not consolidate with or
         merge with or into (whether or not such Guarantor is the surviving
         Person) another corporation, Person or entity whether or not affiliated
         with such Guarantor unless:

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                           (i) subject to Section 11.05 of the Indenture, the
         Person formed by or surviving any such consolidation or merger (if
         other than a Guarantor or the Company) shall be a corporation organized
         and validly existing under the laws of the United States or any state
         thereof or the District of Columbia, and unconditionally assumes all
         the Obligations of such Guarantor, pursuant to a supplemental indenture
         in form and substance reasonably satisfactory to the Trustee, under the
         Notes, the Indenture and the Guarantee on the terms set forth herein or
         therein;

                           (ii) immediately after giving effect to such
         transaction, no Default or Event of Default exists; and

                           (iii) the Company would be permitted, immediately
         after giving effect to such transaction, to incur at least $1.00 of
         additional Indebtedness (other than Permitted Indebtedness) pursuant to
         Section 4.09 of the Indenture.

                  (b) In case of any such consolidation, merger, sale or
         conveyance and upon the assumption by the successor Person, by
         supplemental indenture, executed and delivered to the Trustee and
         satisfactory in form to the Trustee, of the Guarantee endorsed upon the
         Notes and the due and punctual performance of all of the covenants and
         conditions of the Indenture to be performed by the Guarantor, such
         successor Person shall succeed to and be substituted for the Guarantor
         with the same effect as if it had been named herein as a Guarantor.
         Such successor Person thereupon may cause to be signed any or all of
         the Guarantees to be endorsed upon all of the Notes issuable hereunder
         which theretofore shall not have been signed by the Company and
         delivered to the Trustee. All the Guarantees so issued shall in all
         respects have the same legal rank and benefit under the Indenture as
         the Guarantees theretofore and thereafter issued in accordance with the
         terms of the Indenture as though all of such Guarantees had been issued
         at the date of the execution hereof.

                  (c) Except as set forth in Articles 4 and 5 of the Indenture,
         and notwithstanding clause (a) (iii) above, nothing contained in the
         Indenture or in any of the Notes shall prevent any consolidation or
         merger of a Guarantor with or into the Company or another Guarantor, or
         shall prevent any sale or conveyance of the property of a Guarantor as
         an entirety or substantially as an entirety to the Company or another
         Guarantor.

         6. RELEASES. In the event of a sale or other disposition of all of the
assets of any Guarantor, by way of merger, consolidation or otherwise, or a sale
or other disposition of all to the capital stock of any Guarantor, then such
Guarantor (in the event of a sale or other disposition, by way of merger,
consolidation or otherwise, of all of the capital stock of such Guarantor) or
the corporation acquiring the property (in the event of a sale or other
disposition of all or substantially all of the assets of such Guarantor) will be
released and relieved of any Obligations under its Guarantee; provided that the
Net Cash Proceeds of such sale or other disposition are applied in accordance
with the applicable provisions of the Indenture, including without limitation
Section 4.10 of the Indenture. Upon delivery by the Company to the Trustee of an
Officers' Certificate and an Opinion of Counsel to the effect that such sale or
other disposition was made by the Company in accordance with the applicable
provisions of the Indenture, including without limitation Section 4.10 of the
Indenture, the Trustee shall execute

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any documents reasonably required in order to evidence the release of any
Guarantor from its Obligations under its Guarantee.

         Any Guarantor not released from its Obligations under its Guarantee
shall remain liable for the full amount of principal of and interest on the
Notes and for the other Obligations of any Guarantor under the Indenture as
provided in Article 11 of the Indenture.

         7. NO RECOURSE AGAINST OTHERS. No past, present or future director,
officer, employee, incorporator, stockholder or agent of each Guaranteeing
Subsidiary, as such, shall have any liability for any Obligations of the Company
or any Guaranteeing Subsidiary under the Notes, any Guarantees, the Indenture or
this Supplemental Indenture or for any claim based on, in respect of, or by
reason of, such Obligations or their creation. Each Holder of the Notes by
accepting a Note waives and releases all such liability. The waiver and release
are part of the consideration for issuance of the Notes. Such waiver may not be
effective to waive liabilities under the federal securities laws and it is the
view of the Commission that such a waiver is against public policy.

         8. NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW YORK
SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE WITHOUT GIVING
EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT THAT THE
APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED THEREBY.

         9. COUNTERPARTS. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of them
together represent the same agreement.

         10. EFFECT OF HEADINGS. The Section headings herein are for convenience
only and shall not affect the construction hereof.

         11. THE TRUSTEE. The Trustee shall not be responsible in any manner
whatsoever for or in respect of the validity or sufficiency of this Supplemental
Indenture or for or in respect of the recitals contained herein, all of which
recitals are made solely by each Guaranteeing Subsidiary and the Company.

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         IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed and attested, all as of the date first above
written.

                                  DAYTON SUPERIOR CORPORATION, as Issuer

                                  By: /s/ Steven C. Huston
                                      ------------------------------------------
                                  Name: Steven C. Huston
                                  Title: Vice President, General Counsel and
                                         Secretary

                                  SYMONS CORPORATION, as Guaranteeing Subsidiary

                                  By: /s/ Steven C. Huston
                                      ------------------------------------------
                                  Name: Steven C. Huston
                                  Title: Secretary

                                  DUR-O-WAL, INC., as Guaranteeing Subsidiary

                                  By: /s/ Steven C. Huston
                                      ------------------------------------------
                                  Name: Steven C. Huston
                                  Title: Secretary

                                  TREVECCA HOLDINGS, INC., as Guaranteeing
                                  Subsidiary

                                  By: /s/ Steven C. Huston
                                      ------------------------------------------
                                  Name: Steven C. Huston
                                  Title: Secretary

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                                  AZTEC CONCRETE ACCESSORIES, INC., as
                                  Guaranteeing Subsidiary

                                  By: /s/ Steven C. Huston
                                      ------------------------------------------
                                  Name: Steven C. Huston
                                  Title: Secretary

                                  DAYTON SUPERIOR SPECIALTY CHEMICAL CORP., as
                                  Guaranteeing Subsidiary

                                  By: /s/ Steven C. Huston
                                      ------------------------------------------
                                  Name: Steven C. Huston
                                  Title: Secretary

                                  SOUTHERN CONSTRUCTION PRODUCTS, INC., as
                                  Guaranteeing Subsidiary

                                  By: /s/ Steven C. Huston
                                      ------------------------------------------
                                  Name: Steven C. Huston
                                  Title: Secretary

                                  THE BANK OF NEW YORK, as Trustee

                                  By: /s/ Cynthia Chaney
                                      ------------------------------------------
                                  Name: Cynthia Chaney
                                  Title: Vice President